Neuroprotective methods and reagents

Abstract

One aspect of the present application relates to a method for limiting damage to neuronal cells by ischemic or epoxic conditions, e.g., such as may be manifest by a reduction in brain infarct volume, by administering to an individual a hedgehog therapeutic or ptc therapeutic in an amount effective for reducing cerebral infarct volume.

1 . A method for prophylactically limiting damage to neuronal cells by ischemic or hypoxic conditions, comprising systemically administering to an individual in need thereof an effective amount of an agent for promoting hedgehog signaling to prophylactically protect cells and limit damage to neuronal cells by ischemic or hypoxic conditions, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         2 . A method for prophylactically protecting cerebral tissue of a mammal against the repercussions of ischemia which comprises systemically administering to a mammal in need thereof a therapeutically effective amount of an agent for promoting hedgehog signaling to prophylactically protect cerebral tissue in said mammal, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         3 . A method for treating cerebral infarction, comprising systemically administering to a patient in need thereof a therapeutically effective amount of an agent for promoting hedgehog signaling for reducing cerebral infarct volume, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         4 . A method for treating cerebral ischemia which comprises systemically administering to a patient in need thereof a therapeutically effective amount of an agent for promoting hedgehog signaling, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         5 . A method for the treatment of stroke which comprises systemically administering to a patient in need thereof a therapeutically effective amount of an agent for promoting hedgehog signaling, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         6 . A method for the treatment of transient ischemic attack which comprises systemically administering to a patient in need thereof a therapeutically effective amount of an agent for promoting hedgehog signaling, wherein the agent for promoting hedgehog signaling is selected from a mammalian Sonic hedgehog polypeptide or a protein kinase A (PKA) inhibitor that selectively inhibits PKA activity over protein kinase C (PKC) activity. 
     
     
         7 . The method of  claim 1 , wherein the agent for promoting hedgehog signaling binds to patched and mimics hedgehog-mediated patched signal transduction. 
     
     
         8 . The method of  claim 7 , wherein the agent for promoting hedgehog signaling is a small organic molecule. 
     
     
         9 . The method of  claim 1 , wherein the agent for promoting hedgehog signaling mimics hedgehog-mediated patched signal transduction by altering the localization, protein-protein binding and/or enzymatic activity of an intracellular protein involved in a patched signal pathway. 
     
     
         10 . The method of  claim 1 , wherein the agent for promoting hedgehog signaling alters the level of expression of a hedgehog protein, a patched protein or a protein involved in the intracellular signal transduction pathway of patched. 
     
     
         11 . The method of  claim 9 , wherein the agent for promoting hedgehog signaling is an inhibitor of protein kinase A (PKA), which inhibitor of PKA inhibits PKA activity at least one order of magnitude more strongly than protein kinase C (PKC) activity. 
     
     
         12 . The method of  claim 11 , wherein the PKA inhibitor is a 5-isoquinolinesulfonamide. 
     
     
         13 . The method of  claim 12 , wherein the PKA inhibitor is represented in the general formula: 
       
         
           
           
               
               
           
         
       
       wherein,
 R 1  and R 2  each can independently represent hydrogen, and as valence and stability permit a lower alkyl, a lower alkenyl, a lower alkynyl, a carbonyl (such as a carboxyl, an ester, a formate, or a ketone), a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate), an amino, an acylamino, an amido, a cyano, a nitro, an azido, a sulfate, a sulfonate, a sulfonamido, —(CH 2 ) m , —R 8 , —(CH 2 ) m —OH, —(CH 2 ) m —O-lower alkyl, —(CH 2 ) m —O-lower alkenyl, —(CH 2 ) n —O—(CH 2 )  m —R 8 , —(CH 2 ) m —SH, —(CH 2 ) m —S-lower alkyl, —(CH 2 ) m —S-lower alkenyl, —(CH 2 )—S—(CH 2 ) m —R 8 , or 
 R 1  and R 2  taken together with N form a heterocycle (substituted or unsubstituted); 
 R 3  is absent or represents one or more substitutions to the isoquinoline ring such as a lower alkyl, a lower alkenyl, a lower alkynyl, a carbonyl (such as a carboxyl, an ester, a formate, or a ketone), a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate), an amino, an acylamino, an amido, a cyano, a nitro, an azido, a sulfate, a sulfonate, a sulfonamido, —(CH 2 ) m , —R 8 , —(CH 2 ) m —OH, —(CH 2 ) m —O-lower alkyl, —(CH 2 ) m —O-lower alkenyl, —(CH 2 ) n —O—(CH 2 ) m —R 8 , —(CH 2 ) m —SH, —(CH 2 ) m —S-lower alkyl, —(CH 2 ) m —S-lower alkenyl, —(CH 2 )—S—(CH 2 ) m —R 8 ; 
 R 8  represents a substituted or unsubstituted aryl, aralkyl, cycloalkyl, cycloalkenyl, or heterocycle; and 
 
       n and m are independently for each occurrence zero or an integer in the range of 1 to 6. 
     
     
         14 . The method of  claim 11 , wherein the PKA inhibitor is selected from the group consisting of N-[2-((p-bromocinnamyl)amino)ethyl]-5-isoquinolinesulfonamide, KT5720, and PKA Heat Stable Inhibitor isoform α. 
     
     
         15 . The method of  claim 3 , wherein the patient is treated prophylactically. 
     
     
         16 . The method of  claim 5 , wherein the patient is treated prophylactically. 
     
     
         17 . The method of  claim 6 , wherein the patient is treated prophylactically. 
     
     
         18 . The method of  claim 3 , wherein the patient is hypotensive. 
     
     
         19 . The method of  claim 3 , further comprising administering one or more of an anticoagulant, an antiplatelet agent, a thrombin inhibitor, and/or a thrombolytic agent. 
     
     
         20 . The method of  claim 3 , wherein the agent for promoting hedgehog signaling inhibits the activity of PKA, cAMP, or adenylate cyclase. 
     
     
         21 . The method of  claim 1 , wherein the agent for promoting hedgehog signaling agonizes the activity of cAMP phosphodiesterase. 
     
     
         22 . The method of  claim 3 , wherein the therapeutically effective amount of the agent for promoting hedgehog signaling does not have a statistically significant affect on blood pressure. 
     
     
         23 . The method of  claim 1 , wherein the mammalian Sonic hedgehog polypeptide comprises an amino acid sequence that (a) binds to a naturally occurring patched protein and promotes hedgehog signaling and (b) corresponds to the amino acid sequence of an N-terminal portion of a naturally occurring Sonic hedgehog protein having a molecular weight of approximately 19 kDa, and wherein the PKA inhibitor inhibits PKA activity at least one order of magnitude more strongly than protein kinase C (PKC) activity. 
     
     
         24 . The method of  claim 23 , wherein the therapeutically effective amount of the agent for promoting hedgehog signaling does not have a statistically significant affect on blood pressure. 
     
     
         25 . The method of  claim 23 , wherein the agent is a mammalian Sonic hedgehog polypeptide comprising an amino acid sequence that (a) binds to a naturally occurring patched protein and promotes hedgehog signaling and (b) corresponds to the amino acid sequence of an N-terminal portion of a naturally occurring Sonic hedgehog protein having a molecular weight of approximately 19 kDa. 
     
     
         26 . The method of  claim 23 , wherein the agent is a PKA inhibitor that inhibits PKA activity at least one order of magnitude more strongly than protein kinase C (PKC) activity. 
     
     
         27 . The method of  claim 2 , wherein the mammalian Sonic hedgehog polypeptide comprises an amino acid sequence that (a) binds to a naturally occurring patched protein and promotes hedgehog signaling and (b) corresponds to the amino acid sequence of an N-terminal portion of a naturally occurring Sonic hedgehog protein having a molecular weight of approximately 19 kDa, and wherein the PKA inhibitor inhibits PKA activity at least one order of magnitude more strongly than protein kinase C (PKC) activity. 
     
     
         28 . The method of  claim 3 , wherein the mammalian Sonic hedgehog polypeptide comprises an amino acid sequence that (a) binds to a naturally occurring patched protein and promotes hedgehog signaling and (b) corresponds to the amino acid sequence of an N-terminal portion of a naturally occurring Sonic hedgehog protein having a molecular weight of approximately 19 kDa, and wherein the PKA inhibitor inhibits PKA activity at least one order of magnitude more strongly than protein kinase C (PKC) activity.